Pneumatically operated sealing device,more particularly for tannery drums



March 17, 1970 M, c ET AL 3,500,584

PNEUMATICALLY OPERATED SEALING DEVICE, MORE PARTICULARLY FOR TANNERY DRUMS Filed April 2, 1968 2 Sheets-Sheet 1 March 17, 1970 R. M. CLERY ET AL 3,500,584 PNEUMATIGALLY OPERATED SEALING DEVICE, MORE PARTICULARLY FOR TANNERY DRUMS Filed April 2, 1968 2 Sheets-Sheet 2 v //1 we far; Way wand )laur/ce Z/aude 67/1 e k/aw e United States Patent 3 500,584 PNEUMATICALLY OPERATED SEALING DEVICE, MORE PARTICULARLY FOR TANNERY DRUMS Raymond Maurice Clery, Roullet, and Claude Ange Maurice Pechdo, Sireuil, France, assignors to Les Tannerles de Sireuil, Sireuil, Charente, France Filed Apr. 2, 1968, Ser. No. 718,137 Claims priority, application France, Apr. 6, 1967, 101,713; Mar. 11, 1968, 143,175 Int. Cl. Ed /10; E06b 7/23 US. Cl. 49-209 12 Claims ABSTRACT OF THE DISCLOSURE A device for sealing off an opening, comprises a door slidably mounted before the opening and operated by a set of double-acting pneumatic jacks. An inflatable seal is positioned facing the framing of the opening in such manner that the door be capable of sliding between the seal and the framing.

The present invention relates to a device for sealing off an opening, such as the opening in a tannery drum, and more particularly to a device of this kind in which the door is mounted slidably before the opening and is operated by a set of double-acting pneumatic jacks.

This invention has for its object to' permit leaktight closure of the door against the framing of the opening and to accordingly provide a device of the kind referred to, comprising an inflatable seal positioned opposite the framing of the opening and carried on a fixed frame fast with the framing, the door being capable of sliding between the seal and the framing. p

In a first specific form of embodiment of the invention, the device additionally includes a pressure distribution frame intermediate the inflatable seal and the door itself. Preferably, this frame is movable in a direction perpendicular to the framing. Thus, in the inflated position, the seal applies the door against the framing through the medium of the movable frame, against which it comes into pressure contact, thereby ensuring proper distribution of the door pressure against the framing.

In a second specific form of embodiment, the inflatable seal is positioned directly opposite the sliding door, without an intermediate movable frame.

In accordance with the present invention, the device can moreover include slideways for the door. In the first embodiment referred to, these slideways are carried by the movable frame, and in the second embodiment by the framing of the opening to be obturated. Such slideways ensure correct positioning of the door before the opening. In accordance with the present invention, likewise, the device can include studs which supportthe frame fixedly, the latter being mounted abuttingly against nuts screwed on to said studs, the contact pressure being exerted by springs working in compression and reacting against the framing. Such an arrangement ensures reliable operation even in the event of the inflatable seal becoming inoperative owing to a leak therein or protracted failure of the compressed air supply, through maintenance of the leaktightness by tightening said nut and compressing the springs.

In the first embodiment referred to hereinabove the movable frame can slide on the studs and the springs can bear against said frame, the action of the springs thereby also facilitating deflation of the seal. In the second form of embodiment, the springs bear directly against the sealcarrying frame. In the case of the door of a rotating tannery drum, either embodiment facilitates opening thereof regardless of whether it is in the top or bottom position.

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Likewise in accordance with the present invention, the device includes an electropnenmatic control circuit comprising a distributor which feeds the jacks alternately for retraction or extension thereof. Preferably, the supply to the seal is controlled by a valve operating at the end of the closing movement of the door, and the device preferably includes in addition a time-delayed relay on the jack-extending feed line to permit deflation of the seal prior to opening of the door.

The device can lastly include, in accordance with the present invention, handles for manual actuation of the door, such handles being notably used in the event referred to of failure of the jack-operating compressed air.

Further particulars of the invention will emerge from the description which follows with reference to the accompanying non-limitative exemplary drawings, in which:

FIGURE 1 is a side view of a first embodiment of a sealing device according to the invention equipping a partly illustrated tannery drum.

FIGURE 2 is a left-hand view on an enlarged scale, on a section through the line II-II of FIGURE 1, with cutaway of the centre portion.

FIGURE 3 is a diagram showing the distributor system in the electro-pneumatic control circuit of FIGURE 1. FIGURE 4 shows an alternative embodiment of the subject device of the invention.

FIGURE 5 is a left-hand view on an enlarged scale, on a section through the line VV of FIGURE 4, with cutaway of the middle portion.

The sealing device shown in FIGURES 1 to 3 is mounted on a tannery drum 1 supported by journals 2 rotating in bearing housings 3. The drum 1 is formed with an opening to be obturated 4, bounded by a framing 5 which is fitted on to the drum body and formed with a flat face 6 receiving a conventional extruded seal 7 of round section. U The device includes a door 8 movable parallel with the plane of the framing 5, a guide-frame 9 for the door 8 movable perpendicularly to framing 5, and a fixed thrust frame 10 having external stiffeners 11 and an internal inflatable seal 12 adapted to contact movable frame 9. The door is a solid rectangular plate and the fixed and movable frames are plates embodying, opposite the opening, recesses 13 and 14 of the same diameter as that of the opening and carrying, at their peripheries, drilled lugs 15 and 16 which are threaded over rods 17 fast with framing 5 and perpendicular thereto. The moving frame lugs 16 have guide bushes 18 thereon sliding along the rods 17 and springs 19 working in compression coiled round the bushes 18 and butting against the lugs 15 and the framing 5, and these springs are in turn guided within sockets 20 rigid with framing 5. The fixed frame is restrained on the rods 17 by nuts 21 screwed over the threaded ends 22 thereof. The inflatable seal is disposed along the perimeter of the central recess in the fixed frame and its free face 23 contacts movable frame 9. This inflatable seal is of rectangular section and, on its side adjacent the fixed frame 10, is formed with a peripheral projection 24 which is restrained by a double ring 25 against fixed frame 10.

The drum structure further carries two horizontal slideways 26 for guiding the door movement, which movement is likewise guided by two horizontal guiding irons 27 projecting from movable frame 9 on its side remote from seal 12. The drum structure further carries two double-acting pneumatic jacks whose cylinders 28 are fixed horizontally, respectively above and below the framing 5, and whose piston rods 29 are fast with a vertical member 30 fixed to the outer end of the door, that is to say on the same side as slideways 26.

The electropneumatic control circuit includes a pneumatic circuit which comprises, extending from a compressed air supply line 31, two control lines 32 and 33 which pass through one of the drum journals 2 via conventional rotary seals 34, the line 32 being connected to the two front chambers of the jacks, to wit those on the slideway side, and the line 33 to their two rear chambers. The line 32 is further connected through a branch line 35 to inflatable seal 12. Connected into branch line 35 is a follower-wheel-carrying microvalve 36 adapted to cooperate with a ramp 37 fast with the member 30 and positioned at, the point where ramp 37 is located when door 8 is closed (see FIGURE 1).

The electric control circuit comprises a power supply input means 38 and a switch 39 one of whose terminals 40 is connected to the arm 41 of a selector switch having a resting contact 42 and two working contacts 43 and 44, the former being connected to a closing solenoid 45 connected into pneumatic line 32 and the latter via a timedelayed relay 46 to an opening-solenoid 47 connected into pneumatic line 33. The other terminal 48 of switch 39is connected directly to opening:solenoid 45 and, via time delayed relay 46, to closing-solenoid 47. Time-delayed relay 46 is controlled in addition directly. 01f the electric power input means 38 via lines 49 and 50.

The theory of operation of the device hereinbefore disclosed is as follows.

-When the door is in the open position, that is to say fully-engaged into slideways 26, switch 39 is closed and selector switch arm 41 moved to closing contact 43. Op erationthen becomes automatic: closing-solenoid 45 opens and pneumatic feed line 32 supplies the front jack chambers, thus causing the door to close, being guided by slideways 27. When the door is fully home in its closed position, ramp 37 opens microvalve 36 by coacting with the follower. wheel thereof, thereby causing seal 12 to be deflated.

Through agency of movable frame 9, seal 12 applies the door 8 leaktightly against the seal 7 of framing 5, thus ensuring perfect distribution of the pressure exerted by the door against the countering springs 19.

A safeguard is provided in the closed position by virtue of the fact that in the event of an air failure in the line 31 or a power failure at 38, solenoid 45 performs the function of a sealing valve and maintains the pressure in the jackand inflatable seal circuit. In order to open the door, selector switch arm 41 is moved opening contact 44 and operation becomes automatic once more: closing-solenoid 45 closes, causing closing circuit 32 to be drained. By virtue of the presence of time-delayed relay 46, opening-solenoid 47 does not open immediately, so that opening circuit 33 remains unpressurized and the jack pistons do not move; on the other hand, microvalve 36, which remains open, allows the seal to deflate via the exhaust duct of solenoid valve 45. Once the seal ,hasdeflated and the door has been relieved of its pressure, then because the lag in the opening of the time-delayed relay corresponds to the time required to deflate the seal, solenoid valve 47 opens and sets the rear jack chambers under pressure, thus causing the door to open.

In the description which follows of an alternative constructional form, shown in FIGURES 4 and 5, like parts to those in FIGURES 1 and 2 are designated by like reference numerals followed by the suflix a.

In this alternative embodiment, the drum 1a has an opening 4a bounded by a framing a, and the flat face 6a formed on the latter carries a seal 7a. Slideways 27a fast with said flat face are provided on either side thereof and the movable door 8:: slides therethrough.

Opposite framing 5a is a fixed frame a restrained against studs 17a between restoring springs 19a and nuts 21a. The frame 10a comprises an inflatable seal 12a.

The theory of operation of the alternative constructional form just disclosed is such that when door 8a is slid into the obturating position facing seal 70, the sub- 4 sequent inflating of seal 12a causes it to be leaktightly applied against seal 7a.

This simplified constructional form, which dispenses with the movable frame intermediate the door and the inflatable seal, nevertheless enables the door to be satisfactorily cleared from contact with seals 7a and 12a by the springs 19a. Leaktightness is also satisfactorily maintained, whether in the event of leakage from seal 12a or protracted failure of the compressed air supply to the seal via the line 35a, by virtue of the tightening possibilities ofliered by the nuts 21a on the studs 17a.

In order to provide for manual operation in the event of failure of the compressed air supply, the door 8a has associated thereto handles 30b which are preferably mounted on the member 30a used for interconnecting the door 8a and the rods 29a of jacks 28a.

It goes without saying that many changes and substitutions of parts may be made in the specific embodiments of the present invention hereinbefore disclosed and described, without departing from the scope of the invention.

We claim:.

1. In a device for sealingly obturating an opening. comprising a framing around said opening, a sliding door movable transversely of said opening, door moving means mechanically connected to said door, an inflatable seal positionable facing said framing and a frame carrying said inflatable seal, the improvement wherein said frame is mechanically connected to said framing so as to being not movable transversely of said opening, said frame being formed with a recess therein opposite said opening.

2. .In a device as claimed in claim 1, rods fixed perpendicularly to said framing and slidingly supporting'said frame, nuts screwed on to said rods and having'said frame in pressure contact therewith, and compression springs intermediate" said framing and said frame.

3. In a device as claimed in claim 2, a pressure distributing frame} embodying a recess facing said opening, positioned between said framing and said inflatable seal and slidably. mounted on said rods, said compression springs being positioned between said pressure distributing frame and said framing.

4. In a device as claimed in claim 1, a pressure distributing frame embodying a recess facing said opening, positioned between said framing and said inflatable seal and movable perpendicularly to said framing.

5. In a device for sealingly obturating an opening, comprising a framing around said opening, a sliding door movable transversely of said opening, a guiding door slideway coextensive with said framing and extending beyond the same, door moving means mechanically connected to said door, an inflatable seal positionable facing said framing and on that side of said slideway which is remote therefrom and a frame carrying said inflatable seal, the improvement wherein said frame is mechanically connected to said framing so as to being not movable transversely of said opening, said frame being formed with a recess therein opposite said opening, said seal being positioned intermediate said frame and said slideway.

6. In a device as claimed in claim 5, the fact that said sliding door is supported in said slideway.

7. In a device as claimed in claim 5, a pressure distributing frame embodying a recess facing said opening, positioned between said framing and said inflatable seal and movable perpendicularly to said framing.

8. In a device as claimed in claim 7, the fact that, opposite said framing, said slideway is supported by said pressure distributing frame.

9. In a device for sealingly, obturating and opening, comprising a framing around said opening, a sliding door movable transversely of said opening, a pressure fluid supply, a set of double acting pneumatic jacks mechanically connected to said door and each having a jack rod, a door-opening chamber and a door-closing chamber, an inflatable seal positionable facing said framing and a frame carrying said inflatable seal, the improvement wherein said frame is mechanically connected to said framing so as to being not movable transversely of said opening, said frame being formed with a recess therein opposite said opening.

10. In a device as claimed in claim 9, an electrically operated door-closing valve, an electrically operated door opening valve, an electric selector switch for placing said electrically operated valves in circuit alternately, an electrical connection between said electric switch and said electrically operated door-closing valve, an electrical connection between said selector switch and said electrically operated door-opening valve, pneumatic interconnecting conduits between said door-closing valve and said doorclosing chambers and pneumatic interconnecting conduits between said door-opening valve and said door-opening chambers.

11. In a device as claimed in claim 10, a branch line extending between said inflatable seal and said interconnecting conduits to said door-closing chambers, and a limittravel valve connected into said branch line and operatively actuated at the end of the door-closing motion by a References Cited UNITED STATES PATENTS 2,330,220 9/1943 Kemper 4947'7 X 3,157,307 11/1964 Sullivan et al. 220-46 FOREIGN PATENTS 448,070 4/1948 Canada.

J. KARL BELL, Primary Examiner US. Cl. X.R. 

